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以高效液相色谱法检测方法,对橙皮甙的稳定性进行了初步研究。结果表明:橙皮甙的耐光、耐热性能好,在碱性较强的条件下稳定存在,pH值为12时,其在溶液中的溶解度最大。  相似文献   

3.
《林木和林地权属登记管理办法》 ,已于 2 0 0 0年 1 1月 2日国家林业局第 3次局务会议审议通过 ,现予发布 ,自发布之日起施行。国家林业局局长   周生贤 二○○○年十二月三十一日国家林业局令 第1号  相似文献   

4.
《占用征用林地审核审批管理办法》 ,已于 2 0 0 0年 1 1月 2日国家林业局第 3次局务会议审议通过 ,现予发布 ,自发布之日起施行。  国家林业局局长   周生贤 二○○一年一月四日国家林业局令 第2号  相似文献   

5.
Supplementing the diet of Coeloides scolyticida, Dendrosoter protuberans and Ecphylus silesiacus (Hymenoptera: Braconidae) with Parker's diet and the nectars of melliferous plants: Daucus carota L., Sinapis alba L. and Stachys recta L. had a significant effect on longevity, reproduction, developmental rate, and parasitizing of Scolytus scolytus (Fab.), Scolytus multistriatus (Marsh.) and Scolytus pygmaeus (Fab.) (Coleoptera: Scolytidae). These values were considerably lower for wasps fed with the nectar of Sinapis arvensis L. and Trifolium repens L. and the lowest for those without dietary additives. Parker's diet had the most significant effect on the parasitoids and parasitizing of the bark beetles. Nectar of S. recta and S. alba proved most suitable for C. scolyticida and D. protuberans, while E. silesiacus using the nectar from D. carota flower significantly increased parasitizing of S. pygmaeus. T. repens flowers were not a suitable additive for the diet of parasitoids. The parasitoids without additives in their diet had shorter lives, shorter development, and were less effective in reducing host numbers. E. silesiacus wasps had the longest development, and C. scolyticida the shortest. Generally, the parasitoids of the second generation had a slightly prolonged development (1?–?2 days).  相似文献   

6.
Laboratory bioassay of the two fungiMetarbizium anisopliae (Metschnikoff) Sorokin andVerticillium indicum (Petch) Gams was carried out under 26±1 C° and 75±2% R. H. This is the first study on the efficiency of both mycopathogens against the termiteCryptotermes brevis (Walker). Using the highest concentration ofM. anisopliae (43.5 × 105 V.S/ml), percentages of mortality after 4 weeks from treatment of the termiteC. brevis fed on filter paper or wood were 100 and 93.33, respectively. On the same time, the highest concentration of the fungiV. indicum (34.3 × 105 V.S/ml) resulted in the mortality percentages of 83.33 and 70, respectively, fed on filter paper and wood. In general, the data indicated more susceptibility of the termiteC. brevis to the entomopathogenic fungusM. anisopliae than to the fungusV. indicum. M. anisopliae could be considered as a promising potential mycopathogen against the termiteC. brevis. This study, presenting new approach of the alternative dry wood termite control, might be applied in the future.  相似文献   

7.
The effect of different doses 5, 10, 15, 30, 40 and 50 KR of gamma irradiation on the infectivity ofSteinernema feltiae Filipjev nematode has been studied. It was found thatS. feltiae was inactivated by gamma irradiation. Motility of nematodes as well as the mortality and infestation intensity of the host decreased at the higher doses. Development of nematodes was inhibited at the highest dose. No reproduction of nematodes occurred with any of gamma irradiation doses.  相似文献   

8.
本文根据榆(林)绥(德)高速公路建设路段涉及毛乌素沙地沙丘、黄土丘陵沟壑和无定河河谷三种复杂地貌类型,生态环境极为脆弱的特点;根据高速公路边坡防护植被选择的原则,通过植物根系与边坡岩土体的相互作用等相关试验研究,并参阅大量文献的基础上,研究了植物根系与边坡岩土体的相互作用机理,分析总结了高速公路植被边坡防护效益以及适合该路段边坡防护植被和道路两侧碎落台景观树种的选择。  相似文献   

9.
<正> 因为这些森林直到目前还很少加以经营管理,很难说它们的面积究竟有多大。也许热带雨林的总面积约为8.5亿公顷,蓄积量约为1,250亿立方米,这大致相等于面积比它大得多的北温带林的蓄积量。热带雨林的立木蓄积量(包括枝桠)实际上是高的。但是能达到可利用径级的数量较少,合乎商品材树种规格要求的数量更少。在拉丁美洲的老龄林中每公顷  相似文献   

10.
(接第2期)林业政策分析和制度经济学林业政策目标就是在森林和制度不断变化的环境中,实现复杂的经济、社会和政治目标之间的平衡。因此,政策模型往往是由许多变动因素组成,这些变动因素存在于各种林业法规中,而且还在不同主题(包括林业供给、木材销售和定价、森林税费、国际贸易、森林管理标准、碳汇、热带森林滥伐、林权、产权和政策改革等方面)的政策讨论中出现。尽管我们难以全面的回顾与这些主题相关的论著,但总体而言,这些论著不是以新古典经济学工具为基础,就是以制度经济学为基础。新古典经济学工具已经被用于分析木材供给、木材定价…  相似文献   

11.
Bean-weevil (Bruchus chinensis L.) is commonly found in Sind region of Pakistan and it severely damages Mong seeds (Phaseolus mungo L.), and some other pulses in storage conditions. The parasitoidApanteles flavipes (Cam.), a gregarious Braconid parasite of Bean-weevil was reared under laboratory conditions with a view to exploiting it for the biological control techniques to be reported for the first time in Pakistan. This parasite completes its whole life cycle inside the body of the host by completing a number of generations in a year, and it successfully parasitisesBruchus spp. larvae inside the seed body; and its life cycle entirely depends upon the environmental factors like temperature and humidity as well as on the physiological condition of the host. It parasitised upto 45% in field population and 83% under laboratory conditions.  相似文献   

12.
To further characterize carbohydrate physiology in grapevine flowers, we examined inflorescence autotrophy in the 'Gewurztraminer' and 'Pinot noir' cultivars, which differ in sensitivity to flower abscission. In both cultivars, positive net photosynthesis occurred in inflorescences. The rate of photosynthesis gradually decreased throughout flower development and there was no net carbon assimilation at fruit set. The rate of photosynthesis was positively correlated with chlorophyll concentration but not to stomatal conductance. Throughout flower development, the internal CO2 concentration increased in inflorescence tissues, suggesting that assimilates are also formed through refixation of respiratory CO2 by the phosphoenolpyruvate carboxylase (PEPC) pathway. Significant differences between the two cultivars were recorded during meiosis, when photosynthesis was higher in 'Gewurztraminer'. We conclude that the inflorescence of grapevine contributes to its own carbon nutrition by photosynthesizing throughout flower development. Moreover, the differential patterns of photosynthesis in the inflorescences of 'Gewurztraminer' and 'Pinot noir' might account for their differing fertilization rates and sensitivity to flower abscission.  相似文献   

13.
<正> 较大一部分温带林现在或多或少都在加以采伐利用。由于广泛的铁路、公路和水路交通设施,人们可以进入许多林区。因此,很多森林的结构、蓄积量和生长率均在某种程度上反映着它们受到的利用和经营上影响。  相似文献   

14.
原柳属Pleiarina Rafin.隶属于杨柳科柳亚科Salicaceae subfam.Salicoideae;在柳亚科的系统发育中,它体现了一条单独的演化路线、代表了一个明确的谱系分枝;它自然分布于大约从南纬52度至北纬70度的非洲、南美洲、欧洲、亚洲、北美洲的广大地区,广泛生长在热带、南温带、北温带、北寒带(南缘)的各个地带。原柳属约有56个天然种,本文中被区分为2个亚属、6个组、3个系;原柳亚属Subgen.Pleiarina包含4个组,即四籽柳组Sect.Tet-raspermae,原柳组Sect.Pleiarina(包含原柳系Ser.Pleiarina,腺柳系Ser.Glandulosae,锐叶柳系Ser.Acmophyllae),马达柳组Sect.Madagascarienses和锦江柳组Sect.Fangianae;五蕊柳亚属Subgen.Lygus包含2个组,即五蕊柳组Sect.Lygus和三蕊柳组Sect.Amygdalinae。编写了亚属、组、系的检索表。提供了原柳属植物种类一览,包括它们的正名、异名、文献引注、地理分布等。  相似文献   

15.
舞毒蛾卵平腹小蜂发育与温度的关系及子代性比控制   总被引:1,自引:0,他引:1  
舞毒蛾卵平腹小蜂Anastatus disparis是几种鳞翅目害虫重要的卵寄生蜂。为了在大规模繁殖舞毒蛾卵平腹小蜂时控制小蜂发育进度及繁殖一定雌雄性比的小蜂种群,以柞蚕Antheaea pernyi卵为替代寄主,设置不同的温度梯度,研究该蜂雌雄个体发育与温度的关系,比较交配与未交配雌蜂的子代数量、寿命等差异。结果表明:舞毒蛾卵平腹小蜂雄蜂发育所需有效积温(290.15±3.48)℃低于雌蜂(338.88±3.66)℃,雌雄个体发育起点温度均在13℃左右;子代羽化率与发育温度呈显著正相关;子代雌蜂羽化数量与发育温度,子代雌雄性比与不同温度下的羽化率分别呈正相关性;交配与否对雌蜂所产子代数量、寿命及产卵期无明显影响,但未交配雌蜂一生平均产子代量(332.34±37.47)略低于交配雌蜂的(421.88±37.122);交配雌蜂每日所产子代雌雄性比与雌蜂龄期呈显著负相关关系。总结出室内控制舞毒蛾卵平腹小蜂发育进度、繁殖一定雌雄性比小蜂种群的方法。为保持野外种群结构稳定、提高生防效力,提出"释放与自然种群雌雄性比相近天敌种群"的应用策略。  相似文献   

16.
The effect of gamma irradiation on the pathogenicity of the entomopathogenic nematodeSteinernema carposapsae was studied by infecting the larvae of the potato tuber moth,Phthorimaea operculella. Full grown larvae of the host were gamma-irradiated with different doses ranged from 2.5 to 160 Gray (Gy) and subsequently infected with either unirradiated or irradiated infective juveniles (IJs) ofS. carpocapsae using the same doses. For comparison, two groups of unirradiated and irradiated host larvae were left without nematode infection. Another group of larval host was also infected with nematodes either unexposed or exposed to the previous doses.The results revealed that there was a rapid mortality in the irradiated host infected with either unexposed nematodes or nematodes irradiated with different doses similar to the mortality in the nematode treatment alone. On the other hand, the pathogenicity of the nematodes was affected as a result of gamma irradiation with high doses, i. e. irradiation of nematodes delayed their efficiencyvis à vis the unirradiated host. However, lower doses of gamma irradiation exhibited worthily stimulating effect on the pathogenic nematodes, one week post irradiation, as it reduced by half the period of time required for killing all irradiated host larvae with regard to nematode treatment alone. Furthermore, nematode treatment whether applied alone or combined with gamma irradiation appears very promising as compared with single irradiation treatment of the host.With 3 tables  相似文献   

17.
Rearing ofEpiricania melanoleuca (Fletcher) on adult females ofPyrilla perpusilla (Walker) augmented the productivity of the former, which is an effective nymphal and adult ectoparasitoid of the latter, in terms of yield of total and viable eggs. The applied value of this finding in field biocontrol program is highlighted.
Zusammenfassung Wurden die ektoparasitischen Raupen vonEpiricania melanoleuca auf adulten Weibchen der Zuckerrohr-Zikade,Pyrilla perpusilla aufgezogen, vergrößerte sich die Zahl und Lebensfähigkeit der Eier, die von den daraus resultierenden Faltern abgelegt wurden. Das Ergebnis wird im Hinblick auf einen Einsatz des Parasitoiden zur biologischen Bekämpfung des Schädlings erörtert.


With one table  相似文献   

18.
The braconid parasitoidMeteorus rubens (Nees) is a gregarious larval parasitoid ofAgrotis ipsilon (Hufn.). An olfactometer was used to check the attractiveness of the parasitoid to Hexane extract (kairomone) of its host that could be used in conjunction with releases of natural enemies. Female wasps are attracted in high numbers to the kairomone, compared with males. Respective rates of 94.3 and 22.3% are reported. In the control (no kairomone was used), the corresponding figures are 5.7 and 3.3%.  相似文献   

19.
寄生植物肉苁蓉对寄主梭梭生长及生物量的影响研究   总被引:16,自引:3,他引:16       下载免费PDF全文
在新疆吉木萨尔林木良种试验站肉苁蓉繁育基地,以接种肉苁蓉并采收肉苁蓉种子的寄主梭梭(处理A)和未接种成功的即没有被肉苁蓉寄生的梭梭(CK)为调查对象,分别测定其树高、地径、冠幅、生物量和根系;同时,对处理A和CK以及接种成功但肉苁蓉尚未出土的梭梭(处理B)当年生枝的生长量进行定期连续测定。结果表明:处理A的梭梭树高、地径和冠幅,普遍小于CK,且个体间差异较大;总生物量比CK减少了49.29%,其中当年生枝、2年生以上活枝、主干、根系分别降低了22.6%、9.6%、2.2%、15.6%,但枯枝的生物量却高出1倍之多,表现出衰弱的态势;梭梭被肉苁蓉寄生以后,细根所占比例较高,这可能是梭梭为了维持生存和供给肉苁蓉营养采取的一种生态对策,当年生枝的生长却受到一定程度的抑制。  相似文献   

20.
The parasitoids of Gelechia senticetella (Stgr.) (Lepid.: Gelechiidae), a pest of Juniperus excelsa M.?B., were studied in the “Tissata” reserve in Bulgaria. They were reared in laboratory conditions from pest larvae and pupae collected in 1991, 1992 and 2000. As a result of this study, 16 species of parasitoids of G. senticetella were recorded: Habrobracon stabilis Wesm., Hormius moniliatus (Nees), Phanerotoma tritoma Marsh. (Hym.: Braconidae), Diadegma consumptor (Grav.), Liotryphon cydiae (Perk.), Scambus pomorum (Ratz.), Scambus foliae (Cush.), Pimpla turionellae (L.), Eudelus simillimus (Tasch.), Mesochorus sp. (Hym.: Ichneumonidae), Sympiesis acalle Walk., Aprostocetus sp. (Hym.: Eulophidae), Eupelmus urozonus Dalm. (Hym.: Eupelmidae), Copidosoma thompsoni Merc. (Hym.: Encyrtidae), Calliprymna bisetosa Grah., and Mesopolobus sp. (Hym.: Pteromalidae). H. stabilis and P. tritoma were discovered as new species for the fauna of Bulgaria. Three species (E. simillimus, Mesochorus sp. and Aprostocetus sp.) are hyperparasitoids, and the remaining species are primary parasitoids. Most of the parasitoid species attack the larvae of G. senticetella and kill the hosts before pupation. In the studied parasitoid complex, D. consumptor and H. moniliatus were the dominant species. In 1991, the level of total parasitism of the host in the “Tissata” reserve was 24.3?%, in 1992 – 57.9?% and in 2000 – 12.7?%. D. consumptor was the most important parasitoid destroying 26.6?% of the pest larvae in 1992.  相似文献   

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